Hitherto, feeding of fluid substances such as liquid food or nutrient preparation using a gastrostomy tube has been carried out for persons whose capability to take food orally by their own abilities is deteriorated due to aging or diseases (hereinafter referred to as a “patient”). The gastrostomy tube includes a tube member to be installed at a hole (fistula hole) for dietary intake provided in a patient's body, an inner fixing member, often a catheter balloon, fixed to a distal portion of the tube member and installed inside of a stomach wall and an outer fixing member mounted to a proximal portion of the tube member and installed on the side of the body skin. When inserting or taking out the gastrostomy tube into/from the hole formed on the patient's body, operation for insertion and taking-out thereof is performed by a gastrostomy tube extension device, as disclosed in JP-T-2000-507134.
The gastrostomy tube extension device includes a pushing rod which can be inserted into and taken out from a fluid substance feed hole formed on the gastrostomy tube, and an engaging member including an outer fixing member engaging portion which can engage the outer fixing member of the gastrostomy tube and a finger hook on which a finger can be hooked. The inner fixing member is formed at the center of the distal end thereof with a pushing rod engaging portion with which the distal portion of the pushing rod can engage, so that the inner fixing member is elongated when the pushing rod is inserted into the fluid substance feed hole and the pushing rod engaging portion is pushed toward the distal end.
Therefore, when the pushing rod is pushed into the fluid substance feed hole while pulling the finger hook of the engaging member toward the outside (toward the proximal side of the gastrostomy tube) with fingers while the outer fixing member engaging portion of the engaging member is engaged with the outer fixing member, the inner fixing member can be elongated and narrowed. Then, since the inner fixing member in this narrowed state can pass through the hole formed on a patient's abdominal part, the gastrostomy tube can be placed in or taken out from the hole. Also, when the inner fixing member is inserted into the interior of the stomach wall and the force from the pushing rod is released by pulling out the pushing rod, the inner fixing member is brought into a swelled state by its resiliency, and hence the gastrostomy tube does not come out from the patient's body.
When inserting or taking out the aforementioned gastrostomy tube into/from a hole formed on the patient's body, it is necessary to manually maintain the position of the engaging member with respect to the pushing rod constant so that the thickness of the inner fixing member can be kept constant. In other words, with the aforementioned gastrostomy tube extension device, the operation to insert or remove the gastrostomy tube requires great skill by the user, who has to maintain the position by hand. In recent years, it has become more common for “patients” to play a greater role in their personal lives; it is now common for those requiring gastrostomy tubes for themselves or their small children to choose to maintain, and even replace, these tubes without the help of a medical doctor or nurse. This greater role of the patients, however, does require that the insertion/removal of the gastrostomy tubes be relatively uncomplicated to complete.